The following correction was printed in the Observer's For the record column, Sunday July 8 2007

Erskine Childers, author of The Riddle of the Sands, did not take part in the Easter Rising in Dublin in 1916, as we said in the article below, and was not executed as a result. He was secretary-general to the Irish delegation that negotiated the Anglo-Irish Treaty in 1921, creating the Irish Free State. The Treaty divided the new Free State provisional government and Republican Sinn Fein, resulting in civil war. Childers sided with the Republicans and was executed in 1922 for illegal possession of a gun.

In 1894, a Punch illustrator named George du Maurier published a novel set in mid 19th-century Paris describing the adventures in cafe society of an artists' model named Trilby O'Ferrall and her sinister mentor Svengali. Trilby was a succes fou, inspired Puccini's La Boheme and sponsored all kinds of merchandise, including the improbable hat. 'Svengali' entered the language, but the book is now almost forgotten. Trilby is the archetypal zeitgeist novel, the secret of whose astounding success does not really lie with the writer alone.

Now, as we close the long chapter of the Blair decade, is a good moment to look back at the books that did (or did not) capture the Spirit of the Age.

Zeitgeist books often sell many copies, but they are not necessarily bestsellers. They might turn out to be classics, but they do not have to be. A zeitgeist book reflects the spirit of the age in ways that its author and his/her readers don't quite understand. Such books make music in their time in the way a harp makes music from the wind that blows through its strings. These books say something about their time, and are supremely of the moment, but they often survive as curiosities rather than classics. Like Trilby, they can seem incredibly dated and, when we reopen them, their former spell is inexplicable.

After Trilby, candidates for the zeitgeist books of the 1900s include JM Barrie's Peter Pan, Kipling's Kim, Jack London's The Call of the Wild and Erskine Childers' The Riddle of the Sands. The latter spoke directly to its readership: Edwardian society was obsessed with a fear of Germany, and 'invasion scare' stories were often bestsellers. Childers, an Irishman who was executed for his part in the Dublin Uprising of 1916, took a genre and transformed it into popular literature in his brilliant account of sailing the Baltic.

In the decade of the Great War, the favourite reading of the troops was often poetry, but neither Siegfried Sassoon nor Wilfred Owen nor Edward Thomas really qualifies as a zeitgeist author. In fact, it was another thriller, also inspired by the threat of invasion, that became the forces' favourite on the Western Front. John Buchan's The Thirty-Nine Steps of 1915, written in a few weeks during a period of convalescence, is an example of a zeitgeist book that is also a classic.

So, too, is Lytton Strachey's Eminent Victorians of 1918. Declaring that 'discretion is not the better part of biography', he made a ruthless, witty and irreverent demolition of four Victorian icons (Thomas Arnold, Cardinal Manning, General Gordon and Florence Nightingale). Eminent Victorians reprinted six times in its first year of publication; it both reflected and contributed to the postwar mood of cynicism.

In the 1920s, there were many bestsellers (notably John Galsworthy's The Forsyte Saga and PG Wodehouse's The Inimitable Jeeves), but the zeitgeist book is probably Robert Graves's Goodbye to All That, a fierce, self-lacerating account of wartime disillusion. Other contenders for Twenties zeitgeist books also include The Well of Loneliness, All Quiet on the Western Front and The Green Hat

Then there's the conundrum of The Great Gatsby. Many readers might now say that this is the greatest American novel of the century, with almost spooky intuitions about its society. But at the time, despite many good and some indifferent reviews, it was never a big commercial success, its audience largely confined to other, admiring, writers like TS Eliot and Edith Wharton. When F Scott Fitzgerald died of a heart attack in 1940, Gatsby was virtually out of print, neglected and half-forgotten. By then, it had been overtaken by the glossy commercial hits of the Thirties.

In the 1930s, mass-market fiction becomes for the first time dominant in a way recognisable today. On either side of the Atlantic, two huge bestsellers - Margaret Mitchell's Gone With the Wind and Daphne du Maurier's Rebecca - are both strong candidates as zeitgeist books. Gone With the Wind also achieved a unique double: having been a zeitgeist book throughout the run-up to the Second World War, in 1939 it became, overnight, a zeitgeist film, one of the landmark achievements of American cinema. In contrast, Rebecca became so identified with a certain kind of prewar Englishness that the Nazis used an edition of the book as a code source, while Rommel is said always to have kept a copy to hand at HQ.

The shift in mood that took place during the 1940s is reflected in Arthur Koestler's Darkness at Noon and also George Orwell's Nineteen Eighty-Four (1949), whose opening line ('It was a bright cold day in April, and the clocks were striking thirteen') signals a brisk, dystopian vision appropriate to the time. Orwell's satirical inventions (Room 101, newspeak and doublethink) owe much to Swift, but his obsession with politics and language helped the novel's universal appeal. Nineteen Eighty-Four is rare among zeitgeist books in being, by many critical estimates, one of the greatest novels of its century.

It's a short step from Winston Smith to alienation. The Catcher in the Rye (1951) is, among other things, a hymn to teenage angst that is a strong contender for the title of US zeitgeist novel of the 1950s, followed closely by Kerouac's 'beat' novel On the Road (1957). In Britain, we marked the postwar hangover with Lucky Jim, Colin Wilson's The Outsider and William Golding's Lord of the Flies

As we approach our own time, the task of discerning the zeitgeist becomes correspondingly more difficult. From the 1960s, Anthony Burgess's A Clockwork Orange (1962) and Doris Lessing's The Golden Notebook (1962) both have strong claims to perceive an underlying mood, though neither was a big seller on publication. A Clockwork Orange owed most of its success to Stanley Kubrick's 1971 film.

From the paranoid, feminist Seventies, some obvious nominations include Malcolm Bradbury's The History Man (1975), John le Carre's Tinker, Tailor, Soldier, Spy (1974), and from America, Erica Jong's Fear of Flying (1973) and Robert Pirsig's Zen and the Art of Motorcycle Maintenance (1974), a book whose sensational appeal now baffles reason. What could be the appeal of 'the Buddha, the Godhead, resides as comfortably in the circuits of a digital computer or the gears of a cycle transmission as he does at the top of a mountain or in the petals of a flower'? At the time, such words seemed essential.

Zeitgeist books are, by definition, one-offs whose success is owed to a unique configuration of circumstances. Occasionally in this century, there were moments when the kaleidoscope of change was shaken so violently that the world of books became transformed. Such was the effect of radical Toryism in the early 1980s. Midnight's Children might not be a zeitgeist book for the UK, but more widely in the English-speaking world it announced the maturity of a new generation, a multicultural readership looking for a new voice. Rushdie's urgent and mesmerising fabulations were an example to the generation that followed.

Many writers who emerged in Blair's Britain found their first inspiration from novels like Rushdie's early work, and also from Hanif Kureishi's The Buddha of Suburbia. In the maelstrom of social upheaval that characterised the middle years of the Thatcher revolution, if there was one constant it was cash. So Martin Amis's Money stands out not just as a brilliant performance by the greatest stylist of his generation, but also as a novel intuitively in touch with the spirit of the age.

Across the Atlantic, Tom Wolfe's The Bonfire of the Vanities is a more plausible zeitgeist contender, less 'dirty realism' than rehashed Victorianism. Thatcher preferred to relax with the thrillers of Jeffrey Archer. As a philistine who sponsored a renewal of British fiction, her role is one of the more delicious ironies in the zeitgeist books' narrative. The end of Thatcher coincided with Helen Fielding's Bridget Jones's Diary. This scatty romcom connects the 20th century to the new millennium. Who can say why? But that's another story.